Valve mechanism for expression-controlling devices of musical instruments



May 5, 1925. 4 1,536,374

T. P. BROWN VALVE MECHANISM FOR EXPRESSION CONTROLLING DEVICES OFMUSICAL INSTRUMENTS Filed NOV, 14, 1922 4 Sheets-Sheet 1 flwiomfzrwwaMay 5, 1925. 1 536 374 T. P. BROWN VALVE MECHANISM FOR EXPRESSIONCONTROLLING DEVICES OF MUSICAL INSTRUMENTS Filed NOV. 14. 1922 4Sheets-Sheet 2 amrajjrom'za May 5, 1925.

1,536,374 T. P. BROWN VALVE MECHANISM FOR EXPRESSION CONTROLLING DEVICESOF MUSICAL INSTRUMEKITS Filed NOV. 14, 1922 4 Sheets-Shut 3 ILIII T. P.BROWN VALVE MECHANISM FOR EXPRESSION CONTROLLING DEVICES OF MUSICALINSTRUMENTS 4 sheets-{Shaw 4 Patented May 5, 1925.

UNITED STATES PATENT OFFICE.

THEODORE P. BROWN, F WORCESTER,

PLAYER ACTION COMPANY, OF WORC OF MASSACHUSETTS.

MASSACHUSETTS, ASSIGNOR TO SIMPLEX ESTER, MASSACHUSETTS, A CORPORATIONApplication filed November 14, 1922. Serial No. 600,858.

To all 20720222 it may concern.

Be it known that I, THEODORE P. BROWN, a citizen of the United States,residing at \Vorcester, in the county of lVorcester and State ofMassachusetts, have invented new and useful Improvements in Valve Mechanism for Expression-Controlling Devices of Musical Instruments, of whichthe following is a specification.

At the present time the leading makers of pneumatically operated, orself-playing pianos, aim to produce musical instruments which enable thepossessor of one to hear, at any time, substantially the sameperformance as that of an eminent pianist. An artists carefully preparedrecord, produced on a recording piano, is duplicated in the form of anote sheet having side or marginal perforations, which note sheet, whenpassing over the tracker bar of a piano having valve-controlledmechanism to cooperate with said side perforations, re sults inrepeating the performance of the artist who made the record, withapproximate reproduction of his technique, tone,

tempo, and. pedaling.

To provide an automatic musical instrument capable of faithfullyportraying the skill of the artist in the expression of human emotions,is the obj ect of the invention. To this end it is essential that theexpression devices of the piano, especially the valves thereof, shall beextremely sensitive to the variations of atmospheric pressure, due tothe passage of the side or expression perforations of the note sheetover the coacting openings in the tracker 'bar. This object is attainedby providing for the greatest degree of speed in the operation of thevalve, and the elimination of practically all lost motion in saidoperation.

Further improvements consist in a simplified construct-ion andarrangement of the valves and conduits; also an arrangement whereby themain valves which control the flow of-air to cause the proper dynamiceffects only open pro rata to the amount of air flowing through tliem;and also an arrangement whereby the opening movement of the valve is inthe direction of the vacuum-induced flow of air.

Of the accompanying drawings forming a part of this specification,-

Figure 1 represents, partly in elevation and partly in section,sufficient parts of the mechanism which include my invention, to enablethe same to be understood.

Figure 2 represents a section on line 22 of Figure 1, and alsoillustrates a striking mechanism of the usual type such as em ployed ina grand piano.

Figure 3 is a view similar to a portion of Figure 1, on a larger scale.

Figure 4 is a view similar to a portion of Figure 2, on a larger scale.

The same reference characters indicate the same parts in all thefigures.

A frame 12 (Figure 1) supports the usual music-roll spool 13 from whichthe note sheet 14 passes, over the tracker-bar 15, to the take-up roll16. The tracker-bar is provided, near each end, with a row of expressionducts 17, and between them is provided with the usual note ducts 18. Thenote sheet has the usual note openings 19, and is provided with side ormarginal ex pression openings 20, corresponding in number (laterallyconsidered) with the number of ports or ducts 17 in the tracker-bar.Each port or duct 17 communicates by a. tube 21 (Figures 2 and 1) with aprimary pneumatic 22. In Figure 1, to avoid confusion of lines, eachtube 21 is mainly indicated by a dot and dash line. And the usual tubesfrom the note ducts 18 are omitted. Their usual arrangement is wellknown.

Each pneumatic 22 controls one of the expression devices employed in theinstrument, and it will be suflicient to describe one of them, forinstance, the one whose tube 21 (indicated at A in Figure 1) isconnected with the duct 17, at the extreme left of the tracker-bar. Saidpneumatic is connected to and supported by the front cover 23 of thewind chest 24, presently described, two ports 25, 20 leading throughsaid cover. A valve 27, having a short stem 28, is mounted toalternately open or close a port 29, open to the atmosphere, and a portwhich communicates with the air chamber 31, which latter has the port26, providing an uncontrolled passageway to the wind chest. One

lit)

side of the air chamber 31 consists of a diaphragm 32, having a centerpiece to contact with the vvalvestem 28. Therspace at the other sideoflthe diaphragm communicates by a port 33 with the tube 21. Ina

by-pass port 34: around the diaphragmis ,lo-

catedf'a restricted ventf35;

lVithin the wind chest 24: is a diaphragm valve 36, one for eachexpression pneumatic,

which cooperates witlr the nippleend of a ith-z conduit 37, the lattercommunicating the interior of the choker bellows 38. The

movable member of said bellows-carries a bellows 38, by .a-channel43,said wind .cliest being divided. in the .middle of the .instru ment by adivision wall-44 (Figure .1

Fastenedto the backboard 45 of the wind chest (Figures 2 and li'are thepneumatics 46, which are or-niay be of the ordinary striker pneumatic;typeused in. player pianos. Associatedwith said neumatics I may employanyordinary system of; wires and levers, for actuating. thev strikersof. the piano action, such system being partially indicated in Figure2,;but unnecessary. to describe in detail;

In Figures 1 and 3, certain capital letters are applied, one adjacenteach tube 21. A description of the operation. ofthe valve mechanismaffected. by ,the reduction of airpressure when an expression opening20in the note sheet passes over the duct 17, at the extreme left of thetracker-bar, will be sufficient forall. The one selected for thisdescription is the mechanism connected with the tube 21 at thepointindicated by the letter A Thetube 21. shown in Figures 2 and a; istobe understood as the one shown at A inFiguresl and 3.

As indicated in Figure 1, the expression-. control'valvemechanisms arearranged. in three g1'oup s,.the one at the left being for the ,bassaccompaniment control, the one. at the right for the trebleaccompaniment control, and the intermediate one for the solo control. Asthe valve mechanisms of the three. groups. are substantially the same,the samereference numerals :are employed in all, with the exponent addedfor those of the middle group, and the expon'ent add ed for thoseof-theright hand group.

The threeprimary valve mechanisms connected with the tubes, indicatedat,A,;F and G, at the left; ,inFigure 1, are connected by tubes,indicated by the dot and dash lines at, with corresponding primary valvemechai nisnis of the; group at the right in said. fig; lire.- for apurpose presently explained;

lhenormal condition oftheentire mecha:

nism is such that when all the expression ducts 17 are. closed by thenote sheet, the pressure in the wind -chest-24 isslightly lower than thepressure in the interior of thechoker bellows 38', and said pressuresare suchthat tl e instrument will play very soft, under the, control of,any note sheet perforations 19 that may beupassing over the note ducts18 of the tracker-bar. in order to increase thepressure on. either thebass or, the treble of the instrument, it is necessary to open a passagethrough one or more of the conduits 37, to permit added pressure to passthrough the choker bellows 38, independently of the. restrictingvalve.39.- Such added PI'GSSUI'GclS effected whenan expressionperforation of the note sheet passes.

over a duct17 in thentrackerrbar, because atmospheric pressure thenactson the.d1a-.

)hra m 32 'overcomin the functionof the.

restricted vent, 35,- said adiaphragmracting on the stem of the valve27,; andmoving the latter from its positionshowninFigure a, so as toclose the port 29, and open ,the passageway 30. Owing to theports 25,26,the pressure becomes equal on both sides-of the diaphragm valve 36,- andrenders the latter neutral in its relation to the conduit 37, againstwhich: it operates, and therefore permits additionalair topass throughthe conduit 37, andso affect the pressure within the choker bellows 38,independently of the action of the valve v39 (Figure3), and thespring-41,: that the increased pressure affects thevacuumin the mainwind chest 42 (theflow of, air being asv indicated by arrows), andcauses allthe, notes playingiin either the. bass ortreble sections ofvthe,.in-. strument to be played with-a littlegreater force whenever anexpression opening. 20 at the left, side of the notesheet is passingover a duct 1?, in the tracker-bar communicating with either one of thetubes 21, indi? cated atA, F andG. The reason why the treble. as. wellas the bass sections ,will be so affected, is due to the tubes 4L7which, as hereinafter explained, connectthe primary valve mechanisms ofsaid two sections. ftis to beunderstood, of course, that. the primaryvalve mechanisms in both sections, and also in the vsolocontrol section,are, indetail, substantially the same as thehone which is fully shown inFigures 2 and 4.

A musical artist frequently accentuates the solo or melo,dy notesindependently of the. accompaniment notes. ln order that suchaccentuation may be reproduced, it is customaryto so. arrangethecxp-ression,de vices and note sheet. perforations. that the pressurein,the solocontrol bellows isalways higher than in the, bass and trebleaccompaniment I control bellows. The improved structure and arrangementof the tie vices hereinbefore, explained enables the above-mentioneddifferences of pressure. to

loo

be effectively utilized in picking out the solo notes, by means of sideperforations 20 in the note sheet, so as to momentarily increase thevacuum pressure on the particular pneumatic 46 that is to play a solonote. Said improved structure includes the diaphragm valves 36, and theconduits 37, and the primary valve system including the diaphragm 32 andthe valve 27. The operation of these parts so as to effect instantaneousaccentuation will now be described.

F or purposes of illustration, assume that in order to play a piecemezzo forte, there are expression openings 20 in the note sheet inposition to cause two of the valves 36 to open two of the conduits 37 inthe solo control section, and one in the bass control section, and onein the treble accompaniment control section. If now a particular note isto be emphasized without affecting the other notes, the note-sheetopening 19, which is to effect playing of that note, is located eitherslightly beyond or behind the line of notesheet openings which effectplaying of the rest of the notes in the chord. Assuming that the solonote to be emphasized is in the treble section of the instrument, one ofa row of special small perforations 20", in the treble side of the notesheet (Figure 1) opens a duct in the tracker-bar which, by a tube 21",causes a pneumatic to effect opening of the large diaphragm valve 36",in the same manner as hereinbefore described, in connection with thediaphragm valves 36. Said valve 36 cooperates with a relatively largeconduit 37", so that when open, a complete and free flow of air ispermitted from the interior of the treble Wind chest 42, thereby causingany note-striking pneumatic connected with that chest to operate withincreased. force.

It will be noticed that in each of the three expression-controlsections, one of the conduits 37, 37, 37 is larger than the others, andthat each diaphragm valve cooperating thereof is also larger than theothers. The primary pneumatics which affect the large diaphragm valves36, 36 of the bass and solo-control sections, are connected by tubesindicated in Figure 1 at E and N, respectively, with ducts in thetracker-bar which are controlled by special side openings in the notesheet. The varying sizes of the conduits and diaphragm valves justdescribed, enable a greater variation in musical effects to be obtainedthan if all were of the same capacity.

By providing the nipples of the conduits 37, so that they extend intothe wind chest 24:, their ends which form valve seats, are so near theopposite wall of the wind chest which supports the diaphragm valves 36,that the latter need to move no farther from their seats than isabsolutely necessary to perform their functions. They only open pro ratato the flow of air passing through the conduits. Said valves 36 have noworking parts associated with them, and they act directly against theends of the conduits.

As has been explained, the front cover Q3 of the wind chest carries allof the diaphragm pneumatics 36 on its inner surface, and is removablefrom position opposite the conduits 37. All of the primary pneumatics 22are also carried by the said cover 23, on the outer surface thereof. Byremoving said cover 23, all of the diaphragm pneumatics 36, and conduits37, can be readily inspected, and this without disturbing the primarypneumatics 22 from their proper relative positions I claim:

1. A valve mechanism for expression-controlling devices for musicalinstruments having wind chests provided with conduits extending intothem, said conduits being of difierent sizes and capacities andpresenting Valve seats at their inner ends, and diaphragm pneumatics ofcorrespondingly different sizes and capacities, positioned upon theopposite wall of said wind chests and constituting valves cooperatingwith said valve seats.

2. A valve mechanism for expression-controlling devices for musicalinstruments having wind chests provided with conduits ex tending intothem, said conduits being of different sizes and capacities andpresenting valve seats at their inner ends, diaphragm pneumatics of conespondingly different sizes and capacities, positioned upon the oppositewall of said wind chests and constituting valves cooperating with saidvalve seats; primary valves for controlling said diaphragm valves, andconnections for effecting actuation of the primary valves by expressionperforations in a note sheet.

3. In a valve mechanism for expressioncontrolling devices for musicalinstruments, a wind chest having a plurality of compartments andprovided with a removable front cover common to all said compartments,diaphragm pneumatic valves carried by said cover, and conduits ofdifferent sizes and capacities extending into the wind chest from therear thereof, with their ends in position to constitute seats for saiddiaplrragm pneumatic valves.

4. In avalve mechanism for expressioncontrolling devices for musicalinstruments, :1. wind chest having a removable front cover, diaphragmpneumatic valve-s carried on the inner side of said cover, primarypneumatics for actuating said valves being supported on the outer sideof said cover, and conduits of varying sizes extending into the windchest from the rear thereof, with their ends in position to constituteseats for said diaphragm pneumatic valves.

. said compartments, conduits of,

5. r In; a ivalvewmechanism for, -eXpressi-on-,, controlling devicesfor; musical instrnments,- I a wind chesthaving a removable front cover,diaphragm pneumatics carried at the inner ,side thereof, 7 primarypneumaties supperted by the .outer. side thereof, said coverha vingports to provide communication between the? primary pneumatics and thespacesboth sides of the diaphragm .pne matics,- andcon duits extendinginto the wind chest from, the .-rear thereof, with their ends impositionto present valveseats for the diaphragm., Pneumatics. V

6.,In a valve mechanism for expressiom controlling devicesvf01:,1m1sical instruments, the combination with the wind chest thereof,having a plurality of chambers capable of retainingpressure ,ot'different intensities, of valvecontrolling means for, each expression 1chamber,; the said chambers having a removable front cover. common toallotthem said removable cover having,a series of expresrsion-controlling primary pnenmaticsi supi ported by the,,.said removablecover, and means formaintaining the same pressure in the individualprimary pneumatic chamber; as exists ,in its corresponding exp ression.chamber. 7 p

7. In avvalve mechanismhfor expressioncontnolling devices for.musicalinstruments, tl'iei con1bination with a wind:chest having severalcompartments therefor a series of eX-, pressionecontrolling primarypneumatics,. each series; of expression controlling primary. pneumaticsbeing in communication with its particular compartment of the windchest, andx ,each primary pneumatic having? an vair chamber. in freecoinmunication with the wind chest, a diaphragm.torming onei side of;said chamber a passageway having, a .valve and leading tothe wind chestsaid; valve ,being in a position-robe, actuated by. said diaphragm, anda port communicating with the spaceat the other side o't' the; dia- 'mfor said valve. 8.311 a valve mechanism for expression. controllingdevices for; musical instnuments, a wind chest having a plur ality oftcom part-ments, a cover boardcommonoto allot,- variable sizes andcapacitiesin each .otsaid compart ments, said conduits extending throughthe front isideiof theback boand of -th'e wind' chest and presentingvalve seats diaphragm.

; pneumatic valves carried on the xback side of said cover board andcoacting 'itlrsaid valve, seats, said diaphragm; pneumatic:valvesbeingof difi'erent sizes and capacities to correspond withrsaidconduits, a-ndrpi 'i mary valve mechanisms secured to the front;sideof saidcover board, and garranged to be controlled vby expressionperforations ofha notegisheet. V I

9.,In avalve mechanism for expressioncontrolling devices for musicalinstruments,-.

ai wind chest provided with a plurality of compartments eacl compartmenthaving in coinmunicatipn therewith a regulating t .beL

connecting the interior of the. -.respective thewbaclr side.,of aremovable front, cover board to coact withssaldhseats, said vfront coverboard, be1ng commoirto allthe compartments L and I .prim ary valvessecured to thecfront side ,of the said, cover board 1 and arranged tobeivcontrolled by. expression ,perforations of a note vsheet.

10. In a NillVfiIIlQCllfilllSlll for expression:v controlling f devices.for musical. instruments,

a windchest. having several di fl'erentv cham-. bers; ca1;)able. ofretaining different given pressures,-said Wind chest havinga rem-ovablefront; cover common to all the chaim hers, conduits extendedintothedsaid chanr bers, and; ,diaphragm pneumatic valves lo cated on,saidremovablefrontcoven and po; sitioned to vengage the {ends ofsaidconduits.

11, Ina valve mechanism for expression-v controllingdevices. formusical. instruments, a wind, chest comprisingc several compartments,each compartment having conduits of diiferent-r sizes andvariable Ycapacities ,exe

tendingdntothem, each of saidconduits be ing arrangedto present a valveseatflat, its inner end, a diaphragm pneinnatic Valve p sitioned on the,op-posite .wall- :of the a wind; chest. and 5: constituting a .,valvecooperating with said :valve seat, I and a primary valve for controllingeacli ot the; said diaphragm- Pne m i lv eifihe ngement of t e saidvalves. and conduits, being such that, thevsaid diaphragm pneumaticvalves inoper-v at omwill only leavetheirqvalve seats pro rata to.the.indi ced fiow 0t aircreated by v their release.

12. In an automatic, musical instrument,,

an} expression device characterized by have in g a commonnvind chest.divided into several compartments,-;each compartment, being capable ofreta n nga g ven pressure by, ineans of a regulatingpneumatic: for each;

compartment,- said regnlating pneumatics be ng posit oned .on: the, backside of thesaid wind Ichest, the said wind xchest; having con duits -iueach of the vcom pa-itinems connects ing the inte ioroftlieisaid windchestwith the interior of the regulating p11eumatics,1 a

front cover for the said gwind chest, said cover, being cominon-to v-all,the compartments and-E having on: its inward, face diaphragm pneumaticVii-13168.1pOS1tl0llQCl to engage the ends of ,said ,conduits, andprimary pneu mateic, means onv the outside of said cover for controllingthe action of said. diaphragm pneumatic valves.-

13., In a regulating devire folcontrolling the expression of automaticmusical instruments, a main wind chest divided into severalcompartments, each compartment being capable of retaining a pressure ofa given intensity, means located on the back side of said Wind chest forregulating a given How of air through the said Wind chest, conduits ofvarious capacities located in the wind chest and communicating with theinterior of said means for regulating the flow of air and diaphragmpneumatic valve means positioned on a removable front cover common toall the compartments of the said Wind chest, said pneumatic diaphragmvalve means being controlled by primary valve means located 011 theoutside of the said cover and connected to the interior of the saidcompartment of the Wind chest and to the interior of the said diaphragmpneumatic valve means the said primary valves 20 controlling theoperation of the said diaphragm pneumatic valve as governed by the notesheet whereby the intensity of the pres sure in a given coi'i'ipartmentoi the expression device is changed as controlled by the said notesheet.

In testimony whereof I have aflixed my signature.

THEODORE P. BROWN.

